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Background Despite an increase in the number of practicing female physicians, gender disparities in academic medicine persist. For investigating gender gap in the transplantation field, this study examined the relationship between gender and authorship among medical and surgical transplant physicians. Materials and methods In this observational study, all original clinical science articles published in the journals of Transplantation, American Journal of Transplantation, and Clinical Transplantation were reviewed from January 2008 to December 2017. Chi-square analysis was used to compare the proportions of female and male authors, and the Cochrane-Armitage test was used for comparisons over time. Results A total of 2530 publications and 2988 individual authors met the inclusion criteria for the study. Male physicians published significantly more articles compared to female physicians as first (67.4% versus 30.4%) and senior authors (82.9% versus 16.2%), respectively. There were increases in the proportion of female first and senior authors between 2008 and 2017. The majority of authors with multiple publications were male (73.6%), specifically male medical physicians (44.3%). Male medical physicians were the most productive in publication amount and authorship positions. Conclusions While research activity among female physicians increased over time, gender disparity continues to exist among female and male physicians in the transplantation field. Academic activity is lower among females in publication amount and authorship positions. These trends emphasize the need to identify barriers to female physician academic productivity within the transplantation field.

BackgroundMyocardial recovery with Left ventricular assistant device (LVAD) therapy is dichotomous with some patients obtaining remission from end-stage heart failure whereas most require transplantation or remain on pump support long term. Our goal was to determine transcriptional and free radical responses to LVAD treatment.MethodsTissues were collected from patients before and after LVAD placement in non-ischemic dilated cardiomyopathy patients (n = 14) along with controls (n = 3). RNA sequencing (RNASeq) analysis quantified transcriptional profiles by using a custom targeted panel of heart failure related genes on the PGM sequencer. The differential expression analysis between groups was conducted using edgeR (Empirical analysis of digital gene expression data in R) package in Bioconductor. Ingenuity Pathway Analysis (IPA) was carried out on differentially expressed genes to understand the biological pathways involved. Electron Paramagnetic Resonance (EPR) Spectroscopy was utilized to measure levels of free radicals in whole blood collected pre- and post-LVAD implantation (n = 16).ResultsThirty-five genes were differentially expressed in pre-LVAD failing hearts compared to controls. In response to LVAD therapy, only Pyruvate dehydrogenase kinase 4 (PDK4) and period circadian protein homolog 1(PER1) were altered with 34 heart failure related genes still differentially expressed post-LVAD compared to controls. IPA showed that DNA methylation-related genes were upregulated in both pre- and post-LVAD and was persistent with a Z-score of 2.00 and 2.36 for DNA Methyltransferase 3A (DNMT3A) and DNA methyltransferase 3B (DNMT3B), respectively. Inhibition of micro RNA21 (mir21) was also significant on pathway analysis in the post-LVAD population with a Z-score of − 2.00. Levels of free radicals in blood of pre- and post-LVAD patients did not change significantly.ConclusionLVAD therapy does not reverse many of the transcriptional changes associated with heart failure. Persistent changes in gene expression may be related to ongoing oxidative stress, continued DNA methylation, or changes in metabolism. PDK4 is a key regulator of glucose metabolism and its increased expression by LVAD therapy inhibited pyruvate metabolism.

Background Myocardial recovery with left ventricular assist device (LVAD) therapy is highly variable and difficult to predict. Next generation ribonucleic acid (RNA) sequencing is an innovative, rapid, and quantitative approach to gene expression profiling in small amounts of tissue. Our primary goal was to identify baseline transcriptional profiles in non-ischemic cardiomyopathies that predict myocardial recovery in response to LVAD therapy. We also sought to verify transcriptional differences between failing and non-failing human hearts. Methods RNA was isolated from failing (n = 16) and non-failing (n = 8) human hearts. RNA from each patient was reverse transcribed and quantitatively sequenced on the personal genome machine (PGM) sequencer (Ion torrent) for 95 heart failure candidate genes. Coverage analysis as well as mapping the reads and alignment was done using the Ion Torrent Browser Suite™. Differential expression analyses were conducted by empirical analysis of digital gene expression data in R (edgeR) to identify differential expressed genes between failing and non-failing groups, and between responder and non-responder groups respectively. Targeted cardiac gene messenger RNA (mRNA) expression was analyzed in proportion to the total number of reads. Gene expression profiles from the PGM sequencer were validated by performing RNA sequencing (RNAseq) with the Illumina Hiseq2500 sequencing system. Results The failing sample population was 75% male with an average age of 50 and a left ventricular ejection fraction (LVEF) of 16%. Myosin light chain kinase (MYLK) and interleukin (IL)-6 genes expression were significantly higher in LVAD responders compared to non-responders. Thirty-six cardiac genes were expressed differentially between failing and non-failing hearts (23 decreased, 13 elevated). MYLK, Beta-1 adrenergic receptor (ADRB1) and myosin heavy chain (MYH)-6 expression were among those significantly decreased in failing hearts compared to non-failing hearts. Natriuretic peptide B (NPPB) and IL-6 were significantly elevated. Targeted gene expression profiles obtained from the Ion torrent PGM sequencer were consistent with those obtained from Illumina HiSeq2500 sequencing system. Conclusions Heart failure is associated with a network of transcriptional changes involving contractile proteins, metabolism, adrenergic receptors, protein phosphorylation, and signaling factors. Myocardial MYLK and IL-6 expression are positively correlated with ejection fraction (EF) response to LVAD placement. Targeted RNA sequencing of myocardial gene expression can be utilized to predict responders to LVAD therapy and to better characterize transcriptional changes in human heart failure.

Left ventricular assist devices are routinely placed for end stage non-ischemic cardiomyopathy patients. Myocardial recovery on therapy is highly variable. Next Generation Sequencing gives us the ability to test for a wide range of damaging mutations. Our objective was to determine the association